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| author | Sergey Vojtovich <svoj@mariadb.org> | 2018-04-03 16:19:37 +0400 |
|---|---|---|
| committer | Sergey Vojtovich <svoj@mariadb.org> | 2018-04-20 17:05:28 +0400 |
| commit | 3dec6c48bce84a6c804f2a714aa899aef8c45f93 (patch) | |
| tree | 97bcb6b0a8a6c2e2c9588fe35e5853def16e0b2c /sql/field.cc | |
| parent | 43ab88f0ea4169f5b1a4681320c4fa5f5423585e (diff) | |
| download | mariadb-git-3dec6c48bce84a6c804f2a714aa899aef8c45f93.tar.gz | |
MDEV-15762 - VARCHAR(0) COMPRESSED crashes the server
Character set safe truncation is done when storing non-empty string in
VARCHAR(0) COMPRESSED column, so that string becomes empty. The code
didn't expect empty string after truncation.
Fixed by moving empty string check after truncation.
Diffstat (limited to 'sql/field.cc')
| -rw-r--r-- | sql/field.cc | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/sql/field.cc b/sql/field.cc index 5b1bea4b803..58b8105c00f 100644 --- a/sql/field.cc +++ b/sql/field.cc @@ -7958,12 +7958,6 @@ int Field_longstr::compress(char *to, uint *to_length, char *buf= 0; int rc= 0; - if (length == 0) - { - *to_length= 0; - return 0; - } - if (String::needs_conversion_on_storage(length, cs, field_charset) || *to_length <= length) { @@ -7981,10 +7975,11 @@ int Field_longstr::compress(char *to, uint *to_length, (*to_length - 1) / field_charset->mbmaxlen); rc= check_conversion_status(&copier, end, cs, true); from= buf; - DBUG_ASSERT(length > 0); } - if (length >= thd->variables.column_compression_threshold && + if (length == 0) + *to_length= 0; + else if (length >= thd->variables.column_compression_threshold && (*to_length= compression_method()->compress(thd, to, from, length))) status_var_increment(thd->status_var.column_compressions); else |